Infant restraint systems, commonly referred to as car seats, are well known and widely accepted as a necessary appliance for transporting infants in motor vehicles such as automobiles. Infant restraint systems generally include a molded plastic shell with a seat portion, a back portion, laterally opposed side wall portions, and a base portion for securing the system in place on the seat of the motor vehicle. Most infant restraint systems are unitary devices wherein the shell and the base portion are integrally formed together. Such systems are designed solely for use in motor vehicles and do not serve multiple functions, such as for transporting an infant when shopping or performing other activities.
A few designs, however, are intended to provide multiple functions and include separable seat-base combinations. One such design has an infant carrier with an aperture configured to engage a spring-mounted bolt on the base. Uncoupling is effected by rotating a handle located in front of the infant to a position wherein the uncoupling means may be within reach of the infant. Another design has a detachable base in which the release mechanism is located on either side of the carrier. To disengage the infant carrier from the base, the user grasps the sides of the carrier with both hands and then depresses two release buttons. This design has the obvious disadvantage that the release buttons require the use of two hands and therefore are not convenient to use and may be subject to sticking, particularly if baby food, formula or other matter becomes lodged within the release mechanism.
Another design has release mechanisms located at the front and rear and at both sides of the base. This design includes a hook at the foot end of the base, slots on the underside of the carrier for receiving corresponding posts on the sides of the base, and a handle at the head end of the base. Mounting of the infant carrier on the base requires positioning the foot of the carrier under the hook, and careful alignment of the posts and slots. To uncouple the carrier from the base, the user pulls the handle at the head end of the base, grasps the head end of the carrier and lifts it from the base, then manipulates the foot end of the carrier from under the hook. This design is complicated and inconvenient to use, since it requires careful alignment to engage the carrier and several cumbersome steps to remove the carrier from the base.
Conventional infant restraint systems, including the above-described convertible designs, generally provide a fixed, reclined position for the infant. It is desirable, however, to be able to adjust the angle of inclination of the carrier to adapt to different situations and to provide more comfortable support for the infant. Conventional infant restraint systems generally require external supports to prop the seat into the desired position. Several child restraint systems offer multiple positions, but these designs are generally complicated to use and expense to manufacture, and are generally not designed for use outside the motor vehicle.
Another important feature for any infant carrier, including convertible carrier/restraint systems, is a pivotable handle assembly. It is desirable that the handle be easily movable to a plurality of positions, including a storage position where the handle is located adjacent the carrier and a carrying position where the handle is located above the carrier. Various mechanisms have been proposed for positioning carrier handles in their desired positions. However, such mechanisms are typically complex and require an inordinate number of parts to effect their operation.
Another disadvantage associated with existing carrier handles is that they typically comprise three sides, i.e., a top surface and opposing vertical side walls. In these designs, the weight of the infant carrier and occupant is generally distributed between the two side walls. With the weight distributed in this manner, transporting the infant for any length of time in an alternate carrying position (such as by grasping the sides of the handle or supporting the carrier on the user's forearm) can cause considerable discomfort to the user.
Another issue with many infant carriers is the orientation of the handle grip relative to the user's body. Typically, the handle grip is positioned such that the palm of the user's hand is facing forward or backward. As one can readily appreciate, this is an awkward position for carrying an infant. With the hand in this position, the arm is turned in an unnatural position and can become easily fatigued. Several designs offer alternate handle grip positions, but these designs are generally difficult to manufacture or cumbersome to use.
Another issue relating to infant restraint systems is the location of the adjustment mechanism on the infant restraint belts. The infant restraint belts of the infant restraint system are typically manually adjusted to provide for the proper belt length depending on the size of the infant. As the infant grows, or as different infants use the infant restraint system, it is necessary to readjust the length of the belts. This is typically performed by manipulating belts and buckles on the back of the infant restraint system. Another difficulty presented by many designs is that it is difficult to thread the motor vehicle seat belt through the base of the infant restraint system.
It is against this background and the desire to solve the problems of the prior art that the present invention has been developed.